16 January 2009

Arctic Sea Ice Update

Posted by Dan Satterfield

With the very cold air over much of the nation, east of the Rockies, I expected to get some Climate Change questions from viewers. I had a very good one today and it is worthy of a blog post.

The question was this:  Is all this cold air causing the Arctic ice pack to recover some from the near record low of last Summer and the all time record the year before?

The answer is no. As a matter of fact the ice coverage is running at near record lows still. This may be a sign of yet another Summer of major melting on the way. You should know that the majority of Arctic ice experts now think we have reached the tipping point and that the ice will continue to decline fairly rapidly.

What is a tipping point?? Let me explain.

Perhaps the most surprising discovery about of our climate in the past 20 years, is that it does not change slowly over time. It can change very rapidly. In a matter of a few years or a decade!

Thinking about climate as if it is a dimmer switch is not really correct.

It’s more like the wall switch for your front porch light. It’s either off or on. If we put pressure on the climate, it may change slightly, then all of a sudden it makes a big jump to a new condition.  Just like putting pressure on the switch to the front porch light. You increase the pressure and suddenly it flips up, and the light goes on!

This is what a tipping point is. Many scientists feel that as far as Arctic sea ice goes, we have passed the tipping point and the climate is no longer conducive to an ice pack in the Summer over the Arctic Ocean. It will melt and perhaps be gone in as little as 40 years.

If  we do go into a period of low solar activity, this might delay it awhile, but it will still happen. Keep in mind that greenhouse gases are not the only thing that affects our climate. Solar changes, volcanoes and slight changes in our orbit around the sun all play a role. So do ocean currents like El Nino. This is why climate is so hard to predict and understand.

A blast of mild air into the Arctic in December actually caused a slight melting of the sea ice.  So the coverage is still unusually low. Just because we have a cold outbreak here in the Eastern USA, means little as far as the Arctic is concerned. Most of this air came from Alaska and Siberia. It’s unusually warm right now in Alaska, and the Western USA. So assuming that just because  we are very cold, the planet itself has gotten colder is very faulty thinking.


That said, I am sure I will get an email from someone asking if I still think we need to worry about our Climate,  since it is so cold. I will refer to them to this post of course! I wonder if they  will read it?

I am appreciative of the fact that you just did!